KR950003683B1 - Trunk bit-error-rate testing method - Google Patents

Abstract

The method that tests the BER(Bit Error Rate) of the digital trunk by installing the TTTU(TDX-10 Trunk Test Unit), and measuring the input pattern of pseudo random pattern transmitted by the TTTU is provided. The TTTu(1) can send and receive data with a switch(2) through a RS232C communication line. The TTTU is connects the TTTU test line to the digital trunk line of the exchange system.

Description

Bit Error Rate Test Method of Digital Trunk Line in Electronic Switching System

1 is an overall system diagram for a bit error rate (BER) test of a digital trunk line.

2 is a loopback call path diagram using only time division switches.

3 is a loopback call path diagram using time division and space division switches.

4 is a test line connection flowchart for the BER test.

5 is a flowchart of a procedure of performing a BER test.

6 is a BER test result processing and trunk line recovery procedure flow chart.

7 is a flow diagram of loopback path configuration for testing.

8 is a flow diagram of a loopback call path recovery procedure.

The present invention relates to a BER test method of a digital trunk line of an electro-electronic exchanger.

In communication between exchange and exchange period, communication network is connected by relay line of exchange and various repeaters and transmission system. Therefore, since the transmission quality of the relay line depends on the transmission quality of the entire switching network, the transmission quality of the relay line should be tested to prevent service interruption caused by the degradation of the relay line. Existing exchanges establish a database of relay lines in the Centralized Automatic Report on Trunk (CAROT) system to test the relay lines, calling the test equipment of the exchanges, and testing equipment and station response devices (FER: Far). Test the transmission characteristics such as transmission loss and noise by connecting the communication lines between end responders, or use detailed test equipment (TIMS: Transmission Imparement Measuring System) to analyze detailed analysis such as impulse noise and transmission loss. Log transfer characteristics were tested. However, as the transmission system and the switching network become digital, it is necessary to measure the digital transmission characteristics of the transmission path. Therefore, in the present invention, a repeater test apparatus (hereinafter referred to as TTTU: TDX-10 Trunk Test Unit) is installed in an exchanger and occupies a relay line to be tested by a command of an electric switchboard (TDK-10) operator. The purpose of the present invention is to provide a method for configuring a loopback path in a large station by transmitting a call number for a large station, and to transmit a pseudo random pattern in TTTU and to measure a pattern input by looping back to test a BER of a digital relay line.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic diagram of a system for testing the BER of a digital trunk line. The TTTU (1) can exchange data with the switchboard (2) through the RS232C communication terminal, and connect the TTTU test line to the digital trunk line of the switchboard. Use it. In the switching center 2, the BER test is performed by looping back the transmitting and receiving end of the relay line.

The switch structure of the TDX-10 switch is composed of the TST structure, and the switch connection between the lines of the same module can be configured by the T-switch only (Figure 2). -A route can be constructed using a switch and an S- switch (Figure 3). In addition, the TDX-10 accommodates FIJ (Front Intra Junctor) to provide a physical loopback channel across a time switch (TSW) to send ringback tone to the calling subscriber when performing general call processing. The loopback path configuration for the BER test of the digital trunk line can be configured by selecting an unused FIJ among these FIJs and constructing the path with the FIJ. To perform the test, the operator inputs the trunk line test command through the TDX-10 exchange's operating terminal, and the exchange prepares the test and requests the test line connection to the TTTU. The BER test is performed by requesting that the loopback route be set up as a large station, and the destination exchange configures the loopback route with the corresponding relay line according to the loopback route configuration request.

4 to 6 are procedures for performing the BER test of the digital trunk line at the originating exchange. When the test operator inputs the trunk line test command, the exchange receives this command (16) and checks the state of the corresponding trunk line (17-18) .If the test operator does not call it, changes the state of the relay line to 'under test' ( 19) After retrieving the information of the corresponding relay line and the power information connected to the relay line from the exchange's database (20), requesting the connection of the test line to the TTTU (21) and waiting for the connection result of the test line (22).

Upon receiving the test result of the test line (24), check the connection result (25), if the connection is normal, occupy the relay line (26-27) and send out the loopback and line call number (28). When the loopback path configuration is completed from the power station (28-29), the call path is connected (30) and the TTTU is required to perform the BER test (31), and the test result is waited (32, 33).

When the exchange receives the test results (34), it requests the recovery of the test line (35), notifies the power station of the relay line recovery (36), disconnects the channel (37), changes the state of the relay line to a serviceable state (38) The test results are output (39), the operator is notified of the test results, and then terminated.

7 to 8 are loopback path configuration procedures performed in the destination exchange.

When the incoming call request is received, it selects an unused FIJ and notifies the calling party that the call is possible (44) .If not, it notifies the incoming call and terminates (49,50). (45-46) After the incoming response notification signal is sent to the calling station (47), it waits for the calling notification of the calling station (48). If the origination recovery notification is received from the originating station, the switch is restored and terminated. (15 to 54)

Through the present invention, it is possible to test the transmission quality of the digital signal in the transmission path by testing the digital transmission characteristics that could not be tested by the existing analog transmission characteristics test for the digitalized transmission path. Therefore, it is possible to provide better quality services to users.

Claims (6)

In the method of performing a BER test of the digital relay line of the electronic switchboard having a relay line test device, when the operator inputs a relay line test command through the operating terminal of the electronic switchboard, the relay switch performs a test preparation after performing the test preparation. In the first step of requesting the test equipment connection, the second step of performing the BER test by requesting to configure the loopback route to the large station.The destination exchange exchanges the loopback route to the corresponding relay line according to the loopback route configuration request. When the third stage and the exchange are configured to receive the test results, they request the restoration of the test line, notify the relay station of the relay line recovery, cut the line, change the state of the relay line to a serviceable state, and output the test result to inform the operator. Digital electronic exchanger having four stages How to perform BER test on a trunk line. The method of claim 1, wherein in the first step, when a test operator inputs a relay test test command, the exchange receives the command (16) and checks the state of the corresponding relay line (17-18). After changing the state of the relay line to 'under test' (19), after retrieving the information of the corresponding relay line and the power connected to the relay line from the exchange database (20), after requesting the connection of the test line to the relay line tester (21) A method for performing a BER test of a digital repeater, comprising: (22) waiting for a connection result of a test line; 2. The method of claim 1, wherein in the second step, upon receiving the connection result of the test line (24) and checking the connection result (25), if the connection is normally performed, the second terminal occupies the relay line (26-27) and transmits a loopback line call number. (28). When the loopback path configuration is completed from the power station (28-29), after connecting the communication paths (30), the trunk line test apparatus requires the BER test to be performed (31) and waits for the test results (32). BER test method of digital trunk line. The method of claim 1, wherein the third step selects an unused Front Intra Junctor (FIJ) upon receiving a loopback call forwarding request and notifies the originating station of the incoming call (44), and connects the receiving end switch and the transmitting end switch. (45-46) After the incoming response notification signal is sent to the calling station (47), waiting for the recovery notification of the calling station (48), if the originating recovery notification is received from the calling station, the switch recovers and terminates (54). Method of performing a BER test of a digital relay line, characterized in that. The method of claim 1, wherein the loopback path is performed through a time division switch and a front intra junction (FIJ). The method of claim 1, wherein the loopback path is performed through a time division switch, a space division switch, and a FIJ.